COVID-19 vaccines from Moderna and Pfizer/BioNTech: Swissmedic approves third vaccination for certain population groups

Bern, 26.10.2021 - Following the approval of the corresponding applications Swissmedic is adapting the prescribing information for the COVID-19 mRNA vaccines from Moderna (Spikevax®) and Pfizer/BioNTech (Comirnaty®). People at especially high risk can receive a booster dose of a vaccine in order to remain adequately protected against severe episodes of COVID-19. In contrast to the Comirnaty vaccine, this booster vaccination with Spikevax is administered as a half dose. Patients with a compromised immune system can receive a third vaccine dose.

Swissmedic has checked the submitted documentation on the third dose and is adapting the product information for especially high-risk population groups and immunocompromised individuals. The latest study data indicate that an additional dose can increase the ability to form antibodies against the coronavirus SARS-CoV-2, particularly in patients with a weakened immune system. Those who are at especially high risk can also benefit from a booster dose. During its meeting in October 2021, the independent Human Medicines Expert Committee (HMEC) backed the agency's decision.

Booster dose for people at especially high risk

In an initial series of vaccinations, both vaccines are administered as two intramuscular injections 3 weeks apart (Comirnaty, 2 x 0.3 ml doses) or a month apart (Spikevax, 2 x 0.5 ml doses). A third vaccination at least 6 months after the second dose may help older people or at-risk patients maintain their level of protection against COVID-19.

The booster dose of Comirnaty (Pfizer) is administered at the same dose level as the first two vaccine injections (0.3 ml), whereas a half dose (0.25 ml) of the COVID-19 vaccine Spikevax (Moderna) is used for the booster injection.

Three-dose schedule for patients with a weakened immune system

For immunocompromised individuals or patients with a suppressed immune response (for example recipients of organ transplants or cancer patients) who have only developed a weak immune response, or none at all, against the coronavirus SARS-CoV-2 after two vaccine doses, a third dose at the same dosage can be administered at least 28 days after the second. Data from a clinical trial with participants who had undergone an organ transplant showed that the third dose improves the immune response compared to the control (placebo) group.

Use and safety of COVID-19 vaccines

Based on the changes made by Swissmedic to the product information, the Federal Commission for Vaccination (FCV) has specified detailed vaccination recommendations for the third dose of COVID-19 vaccines. Swissmedic continues to monitor very closely the benefits and risks of the vaccines for preventing COVID in Switzerland and internationally.

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